Regional anesthesia for vascular surgery: does the anesthetic choice influence outcome?

Contraindications to use of neuraxial anesthesia for lower limb revascularization surgery in adults: a cross-sectional study

PURPOSE

Nonrandomized and some randomized data suggest neuraxial anesthesia may improve outcomes after lower limb revascularization surgery. Nevertheless, the prevalence of contraindications to neuraxial anesthesia in vascular surgery patients is unknown. We aimed to identify the prevalence of patients with contraindications to neuraxial anesthesia, and to derive and validate a case ascertainment algorithm identifying individuals likely to have contraindications.

METHODS

We conducted a historical cross-sectional study of open lower limb revascularization surgeries performed between 2019 and 2021 at The Ottawa Hospital. Medical records were reviewed for demographic data, admission, procedural characteristics, and presence of contraindications to neuraxial anesthesia. Case ascertainment algorithms to predict the presence of absolute contraindications to neuraxial anesthesia were derived and internally validated.

RESULTS

We identified 340 cases. General anesthesia was used in 219 (64.4%) cases, isolated neuraxial (spinal and/or epidural) in 106 (31.2%) cases, and general plus neuraxial in 15 (4.4%) cases. Seventy-eight (22.9%; 95% confidence interval [CI], 18.8 to 27.7) patients had absolute contraindications to neuraxial anesthesia, primarily because of anticoagulation or antiplatelet medication (89.4%); 21 (6.2%; 95% CI, 4.1 to 9.3) had relative contraindications, primarily long anticipated duration of surgery (16/21, 76.2%). We derived and validated three nested case-ascertainment algorithms. Using admission and procedure variables, discrimination was moderate with moderately explained variance, and calibration was inadequate for reliable use. Patient comorbidity and laboratory data did not improve algorithm performance.

CONCLUSION

Most patients undergoing lower limb revascularization surgery did not have absolute contraindications to neuraxial anesthesia. When present, contraindications typically related to anticoagulation. Admission, procedure, comorbidity, and laboratory data did not provide adequate accuracy to ascertain contraindication status.

Anesthetic management for lower extremity vascular bypass procedures: The impact of general or regional anesthesia on clinical outcomes

PURPOSE

Postoperative complications after major surgery, especially vascular procedures, are associated with a significant increase in costs and mortality. Previous studies evaluating general anesthesia versus regional or neuraxial anesthesia for infrainguinal bypass have produced conflicting results. The main aim of the present study is to review current evidence on the application of regional or general anesthesia in patients undergoing infrainguinal bypass surgery and its potential favorable effects on postoperative outcomes.

CONTENTS

Patients undergoing vascular surgery often have multiple comorbidities, and it is important to outline both benefits and risks of regional anesthesia techniques. Neuraxial anesthesia in vascular surgery allows overall avoidance of general anesthesia and does provide short-term benefits beyond analgesia. Previous observational studies suggest that neuraxial anesthesia for lower limb revascularization may reduce morbidity and length of stay. However, evidence of long-term benefits is lacking in most procedures and further work is still warranted.

CONCLUSIONS

Neuraxial anesthesia is usually an effective anesthesia technique for infrainguinal bypass surgery. Elderly patients and those with underlying respiratory problems may display some benefit from neuraxial anesthesia. Further evaluation within institutions should be performed to identify which patients would most benefit from regional techniques. Notably, systemic antithrombotic and anticoagulation therapy is common among this population and may affect anesthetic choices.

The Hitchhiker's Guide to Spine Awake Surgery. The Oxford SAS Protocol and Early Outcomes

OBJECTIVE

Spine awake surgery (SAS) aims to achieve faster recovery times, better outcomes, and a lesser economic impact on society. Our drive to establish SAS was to improve patient outcomes and health economics during the COVID-19 pandemic. After a systematic review and to the best of our knowledge, SAS, the Oxford Protocol, is the first protocolized pathway that aims to train bespoke teams performing SAS safely, efficiently, and in a standardized repeatable fashion. A pilot study was designed around newly derived protocols and simulated training to determine if SAS is a safe and implementable pathway to improve patient outcomes and health economics.

METHODS

We assessed a cohort of 10 patients undergoing one-level lumbar discectomies and decompressions, analyzing the related costs, length of stay, complications, pain management, and patient satisfaction.

RESULTS

The age range of our patients was 46-84 years. Three discectomies and 7 central canal stenosis decompressions were performed. Eight patients were discharged on the same day. All patients gave positive feedback about their experience of SAS. A significant cost saving was made compared to a general anesthesia (GA) overnight stay across the group. No on day cancellations occurred due to lack of bed availability. No patient needed analgesia in the recovery room or needed additional analgesia over and above the SAS e-prescription take home package.

CONCLUSIONS

Our early experience and journey reinforce our drive to push forward and expand on this process. It aligns with the international literature which highlights this approach as safe, efficient, and economical.

Popliteal sciatic nerve block for high-risk patients undergoing lower limb angioplasty: A prospective double-blinded randomized controlled trial

BACKGROUND

To assess the rate of conversion to general anesthesia, sedative and analgesic drug-sparing effects, and complications of popliteal sciatic nerve block (PSNB) compared with a sham block during lower limb angioplasty.

METHODS

A randomized, controlled, double-blinded trial of patients with chronic limb-threatening ischemia (CLTI) who receive PSNB with 0.25% levobupivacaine 20 mL compared with a sham block (control) during lower limb angioplasty. Pain scores, conversion rate to general anesthesia, amount of sedoanalgesia drug usage, complications, and satisfaction with the anesthesia technique by surgeons and patients were assessed.

RESULTS

Forty patients were enrolled in this study. Two of 20 (10%) control group patients were converted to general anesthesia, while none of the patients in the intervention group required general anesthesia (P = .487). Pain scores before PSNB did not differ between the groups (P = .771). After the block, pain scores in the block group were lower than those in the control group: 0 (0, 1.5) (median, interquartile range) and 2.5 (0.5, 3.5), respectively (P = .024). The analgesic effect persisted until immediately after the surgery (P = .035). There was no difference in pain scores at the 24-hours follow-up visit (P = .270). The total propofol and fentanyl dosage requirements, a number of patients who required propofol and fentanyl, side effects, and satisfaction were not different between the groups. No major complications were noted.

CONCLUSIONS

PSNB provided effective pain relief during and immediately after lower limb angioplasty, but did not statistically affect the rate of conversion to general anesthesia, sedoanalgesia drug usage, or complications.

The Role of Physician-Directed Duplex after Brachial Plexus Block in Arteriovenous Fistula Creation

BACKGROUND

Best practice guidelines for dialysis access creation emphasize distal sites and autogenous tissue before more proximal sites and synthetic shunts. Pre-operative vein mapping is a useful modality to evaluate optimal access location; however, vein size is often underestimated secondary to patient hypovolemia, room temperature, and basal vascular tone. Supraclavicular brachial plexus blocks (BPB) are routinely performed to provide surgical anesthesia but also have known vasodilatory effects. Although many surgeons use both techniques, most do not repeat vein mapping after BPB to re-evaluate targets after block-mediated vasodilation. Therefore, we evaluated whether the role of physician-directed vein mapping after BPB resulted in more favorable access creations.

METHODS

All patients who underwent primary ipsilateral access creation with physician-directed post-block duplex between 2017 and 2018 were evaluated. Vein mapping was reviewed for "theoretical access location" using the criterion of >2.5 mm vessels. Fistula preference was analogous to current indications with the following order of preference: wrist radiocephalic, forearm radiocephalic, brachiocephalic, brachiobasilic, and finally prosthetic graft.

RESULTS

Forty-three patients met inclusion criteria. In total, physician-directed duplex after regional block resulted in the creation of higher preference accesses than predicted in 62.8% of patients. In 34.9% the access was at the predicted level and only 2.3% were at a lower preference. Furthermore, there were no differences in the maturation rates between accesses placed at higher preference locations than predicted compared to those at expected sites (74% vs. 79%, P = 0.38). The overall revision rate for higher preference access was 22.2% compared to 23.1% for equal/lower preference accesses. Of those accesses that failed, 83.3% of new accesses were created at the original theoretical location while 17.7% required placement of a lower preference access.

CONCLUSIONS

Physician-directed ultrasound after BPB allows for identification of more preferential targets for access creation compared to pre-operative vein mapping. For access created at more preferential locations than pre-operatively predicted prior to BPB, there was no difference in maturation rates compared to those created at the theoretical vein mapping location.

The Environmental Impact of Orthopaedic Surgery

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There are a growing number of opportunities within the field of orthopaedic surgery to address climate change and investigate ways to promote sustainability.

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Orthopaedic surgeons can take a proactive role in addressing climate change and its impacts within the areas of operating-room waste, carbon emissions from transportation and implant manufacturing, anesthetic gases, and water usage.

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Future studies are needed to further these initiatives on quantifying and decreasing environmental impact and furthering sustainable use of our resources.

Saphenous and sciatic nerve block to treat acute lower limb ischemic pain in the emergency department

Acute limb ischemia (ALI) presents with significant pain that is often refractory to opioid pain management or is present in patients with relative contraindications to opioids. Here we present a case of ALI successfully managed with regional anesthesia using sciatic and saphenous nerve blocks. To our knowledge, this is the first case report of regional anesthesia for ALI performed in the Emergency Department (ED) by Emergency Medicine physicians.

OUP accepted manuscript

Background

The relationship between anaesthetic technique and graft patency after open lower limb revascularization is unclear. The aim of this study was to evaluate the association between 30-day graft patency after elective infrainguinal bypass and anaesthetic technique (regional anaesthesia (RA, i.e. neuraxial and/or peripheral nerve blockade) compared with general anaesthesia (GA)).

Methods

Patients who underwent elective infrainguinal bypass in the 2014–2019 National Surgical Quality Improvement Program Vascular Procedure Targeted Lower Extremity Open data set were included. Excluded patients were those under 18 years old, those who did not receive RA or GA, and/or had an international normalized ratio of 1.5 of greater, a partial thromboplastin time more than 35 s, or a platelet count less than 80 × 10⁹/L. The primary outcome was primary graft patency without reintervention. The relationship between anaesthetic technique and patency was analysed with multivariable logistic regression.

Results

Included were 8893 patients with a mean(s.d.) age of 68(11) years and 31.5 per cent female. Within the cohort, 7.7 per cent (n = 688) patients received RA only, 90.4 per cent (n = 8039) GA only, and 1.9 per cent (n = 166) both GA and RA. In the RA-only group, 91.7 per cent (631 of 688) received neuraxial anaesthesia. The primary patency rate was 93.2 per cent (573 of 615) for RA only, and 91.5 per cent (6390 of 6983) for GA only (standardized mean difference, 0.063). RA was not associated with a higher rate of patency compared with GA (adjusted OR, 1.16; 95 per cent c.i., 0.83 to 1.63; P = 0.378).

Conclusion

There was no association between anaesthetic technique and 30-day graft patency after elective infrainguinal bypass surgery. Further prospective studies would be useful to study the impact of anaesthesia technique on important patient-centred outcomes such as long-term patency and non-home discharge.